Signal for private and Whatsapp for work.
Signal
In the current times Signal is the only viable way on mobile. On PC Matrix is a good alternative for chatrooms with friends.
Signal is mainly used by the people I communicate with. The Founder of Signal is also a known Computer Security expert. The signal protocol itself is also used by WhatsApp, Google Messages and Faccebook Messages.
I just had a look at the telegram privacy policy (https://telegram.org/privacy#8-who-your-personal-data-may-be-shared-with) and compared to signals privacy policy (https://signal.org/legal/) telegrams policy is just not for me.
Element as matrix client. It has some bugs and glitches but is the current best matrix client and the matrix protocol is the best communication protocol i know.
The protocol is open and well documented, it is fast, you can transmit everything from Voice over IP to IoT, it works decentralised and supports end-to-end encryption.
https://spec.matrix.org/latest/ Here ist the specification website if you want to read more